A seven-year-old girl was successfully treated for acute lymphoblastic leukemia. Despite clinical remission she developed a monocular hypopyon which was treated successfully with topical and subtenons steroids. When the hypopyon reappeared, a diagnostic paracentesis revealed leukemic cells and a normal aqueous lactate dehydrogenase. Leukemic ocular infiltration may clinically mimic both neoplastic and inflammatory ocular conditions. The combination of paracentesis and lactate dehydrogenase assay greatly aid in the correct diagnosis.
